Build Antlr4 projects with eclipse java project template.

from：https://shijinglu.wordpress.com/2015/01/22/build-antlr4-projects-with-eclipse-java-project-template/

Posted on January 22, 2015 by shijinglu

Before taking any action, remember to install antlr4 plugin for eclipse, it can be easily found from “Eclipse Marketplace”.
1. Create an antlr4 project. This will create an simple “Hello” antlr4 project.

2. Add java project facet to the project.

3. Eclipse will automatically rebuild the project, see messages in the Console, pay attention to the default antlr-4.4-complete.jar path.

4. Or you can move the antlr4 jar file to your comfortable directory and add it the eclipse build path from therein.

5. Add destination folder of generated java files to the project as source folder.

6. Add some code to test this project, <>

// 
// import ANTLR's runtime libraries
import org.antlr.v4.runtime.*;
import org.antlr.v4.runtime.tree.*;
public class HelloRunner {
	public static void main( String[] args) throws Exception {
		// create a CharStream that reads from standard input
		ANTLRInputStream input = new ANTLRInputStream( System.in);
		// create a lexer that feeds off of input CharStream
		HelloLexer lexer = new HelloLexer(input);
		// create a buffer of tokens pulled from the lexer
		CommonTokenStream tokens = new CommonTokenStream(lexer);
		// create a parser that feeds off the tokens buffer
		HelloParser parser = new HelloParser(tokens);
		ParseTree tree = parser.r(); // begin parsing at rule 'r'
		System.out.println(tree.toStringTree(parser)); // print LISP-style tree
	}
}

7. Runt this HelloRunner.java as java application